Objectives To explore the effect of cadmium exposure and MT-2A single nucleotide polymorphism on birth head circumference of the newborns.

Methods 300 pairs of lying-in women-newborns were selected for questionnaire survey, maternal and cord blood of the subjects were collected respectively to measure the concentration of cadmium by ICP/MS, the MT-2Ars 28366003 single nucleotide Polymorphism were detected by Polymerase chain reaction-restriction fragment length polymorphism.

Results ① Statistically significant associations were found between the-5 A/G core promoter region SNP in the MT2A gene and cadmium levels of lying-in women and newborns. (P < 0.05). ② The cadmium concentration of mother can influence the birth head circumference (P > 0.05). ③ In comparison of birth head circumference in four subgroups defined by cadmium concentration group (high/low) and newborn genotype of MT-2A (AA, AG), it was found that mothers in high cadmium exposure, infants carrying the heterozygote genotype (AG) had significantly birth head circumference reduction (P < 0.05).

Conclusions The MT-2Ars 28366003 single nucleotide Polymorphism is associated with blood cadmium concentration; Prenatal cadmium exposure can reduce the head circumference of newborn, and be modified by MT-2Ars 28366003 single nucleotide Polymorphism.